Flotation of minerals.



' UNITED STATES PATENT OFFICE.

CLEMENT L. PERKINS, PITTSBURGH, PENNSYLVANIA, ASS IGNOR TO METALS RECOVERY COMPANY, OF NEW YORK, N. Y., A CORPORATION OF MAINE.

' ELOTATION OF MINERALS.

No Drawing.

use the same;

This invention relates to the concentration of minerals, such as sulfid ores and the like, (for example, chalco-pyrite with a silicious gangue), by flotation, and is based upon the discovery that improved results can be obtained by carrying out the flotation operation with the addition to the ore or mineral pulp of beta-naphthylamin.

either alone or with the addition of other agents promoting the flotation. The betanaphthylamin is a non-oleaginous solid material which can nevertheless be distributed throughout the ore pulp with such uniformity that minimum amounts are required for effecting the concentration of the mineral by flotation. It is not necessary that the chemically pure beta-naphthylamin be used, but the commercial product can be used in its crude or unrefined state.

In using the beta-naphthylamin it may be added to the ore either alone or in admixture with other agents promoting the flotation, in any suitable manner, so that it will bethoroughly and uniformly distributed throughout the ore pulp. The mixture is then subjected to a flotation operation as in an erdinary' -Callowcell orin apparatus where the air is incorporated in the ore pulp by mechanical agitation. With some ore pulps it may be desirable to add either smallamounts of acids or of alkalis, de pending upon the nature of the ore pulp to be treated, but it will be evident that free acid should not be present to any appreciable extent when the beta-naphthylamin is added. That is to say, if the ore pulp contains free acid, or if acid is preliminarily added thereto, the free acid should not be present when the beta-naphthylamin is added or should not be present to any aprecia 1e extent such as would pm'udice'or destroy the efiect of the beta-naphthylamin,

Specification of Letters Patent.

enters the flotation cell.

Patented Sept. 18, 1917.

Application filed August 2, 1917. Serial No. 184,053.

which is of a basic character, during the flotation operation.

With some ore pulps it is important not only to have no free acid present, but to add sufficient free alkali to give a distinct alkaline reaction to the ore pulp during the flotation operation. Small. amounts of caustic alkali, such as sodium hydrate, or of alkali salts, such as sodium carbonate, may

thus be added, in regulated amounts, to give the ore pulp the proper degree of alkalinity.

The amount of beta-naphthylamin used may vary somewhat, for example, between one-half pound or less and one and onehalf pounds per ton of ore (that is, calcu-,

lated on the weight of the ore and not of the ore pulp). It is characteristic of the invention that the froth obtained is readily broken up and the beta-naphthylamin recovered therefrom so that it is available for use in the treatment of further amounts of ore. That is to say, the circuit water recovered from the concentrate and even-that recovered from the tailings contain notable amounts of the beta-naphthylamin which can be thus returned to the process with resulting economy in the amount required to be added for subsequent operations.

The beta-naphthylamin may be used alone to promote the flotation operation and high grades of concentrates obtained; and the resulting concentrates can be much more easily separated by filtration than the common concentrates obtained by the use of oil as the flotation agent. The action ofthe beta-naphthylamin may, however, be modified or supplemented by adding other agents (such as oils or non oleaginous agents) which promote the flotation and which do not prejudically affect the action of the beta-naphthylamin.

In applying the beta-naphthylamin, ..;it may be introduced into the tube mill in which the ore is being ground, or it may be otherwise introduced into the ore ulp in any suitable way, as, for instancah product with the ore pulp just before it What I claim is:

1. The method of efiecting the concentration of minerals-by flotation, which comprises adding to the mineral pulp a small amount of beta-naphthylamin, and subjecty t digesting It in hot water and mlxing the\ ing the resulting mixture to a flotation operation; substantially as described.

2. The method of effecting the concentration of minerals by flotation, which comprises adding to the mineral pulp a small amount of beta-naphthylamin and other agents promoting the flotation, and subjecting the resulting mixture to a flotation operation; substantially as described.

3. The method of efiecting the concentration of minerals by flotation, which comprises adding to the mineral pulp a small amount of beta-naphthylamin and suflicient alkali to give the ore pulp a distinct alkaline reaction, and subjecting the resulting mixture to a flotation operation; substantially as described.

4. tion of minerals by flotation; which comprises adding to the mineral pulp a small amount of beta-naphthylamin and of oil, and subjecting the resulting mixture to a flotation operation; substantially as described.

In testimony whereof I afiix my signature.

CLEMENT L. PERKINS.

The method of efiecting the concentra-' 

